Encode text
Input
hello
Output
aGVsbG8=
Base64 encoder/decoder (text and files)
Decode and encode Base64 from one screen.
Convert text, files, and Data URLs safely in your browser.
No server upload (processing stays in your browser)
Data URLs supported
UTF-8 text output
Conversion Tool
Switch between Encode, Decode, and Auto Detect, then choose Text or File input from the controls above.
Input data stays in your browser and is never uploaded.
Press Ctrl / Cmd + Enter to run conversion.
Examples
Decode Data URL
Input
data:text/plain;base64,SGVsbG8sIHdvcmxkIQ==
Output
Hello, world!
How to use
- Start with Auto Detect, then enter text or choose a file.
- Switch to Encode or Decode manually when needed.
- After conversion, copy the result or download it.
Encode to Base64
- Convert text or files to Base64.
- Choose output format: Base64 only or Data URL (with MIME).
Decode Base64
- Decode Base64 that includes spaces or line breaks.
- Supports URL-safe Base64 (- and _).
- Choose UTF-8 text output or binary download for decoded data.
Split Data URL
- Automatically split the data:...;base64, header and payload.
- Show MIME and Base64 payload separately with one-click copy.
FAQ
Decoded Japanese text looks garbled
Use "Display as text (UTF-8)" first. If the decoded data is binary, switch to "Treat as binary (download)".
Do you support Data URLs (data:image/...;base64,)?
Yes. The tool automatically separates the data:*;base64, header and payload, and shows the MIME type.
Are files uploaded?
No. Conversion runs entirely in your browser, and files are never uploaded.
Can I decode Base64 with line breaks?
Yes. Enable “Ignore whitespace and line breaks” to decode line-broken Base64.
Do you support Base64URL (- and _)?
Yes. Enable “Accept URL-safe Base64 (- and _)”.
Notes
- When decoded content is shown as text, UTF-8 is used. If the original data uses a different encoding, text may look garbled.
- Large files may take longer depending on browser memory limits.